 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<title>Ajax检测用户名</title> 
<script type="text/javascript" src="ajax.js"></script> 
</head> 
<body> 
<form name="myform"> 
	用户名：<input type="text" name="user" id="user" onblur="checkname();" placeholder="请输入hello"> 
<span id="checkbox"></span> 
</form> 
</body> 
</html> 
